Einstein's energy mass relation

AI Thread Summary
In Einstein's energy-mass relation, the energy unit is Joules, which necessitates that mass be measured in kilograms. The correct answer to the homework question is B, as kilograms are the standard unit for mass in this equation. A Joule is defined in SI base units as 1 kg·m²/s². The discussion confirms that using kilograms aligns with standard practices in physics equations. Therefore, the mass unit in this context must be kilograms.
Hannah1
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Homework Statement


In Einstein's energy mass relation, the unit for the energy released is Joules, this means that the unit for the mass must be

a. g
b. kg
c. it could be either grams or kilograms
d. Newtons


Homework Equations


E = mc2


The Attempt at a Solution


I believe the answer is B. because kg tend to be the standard for equations I've been working on lately.

Am I correct??
 
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Hannah1 said:

Homework Statement


In Einstein's energy mass relation, the unit for the energy released is Joules, this means that the unit for the mass must be

a. g
b. kg
c. it could be either grams or kilograms
d. Newtons


Homework Equations


E = mc2


The Attempt at a Solution


I believe the answer is B. because kg tend to be the standard for equations I've been working on lately.

Am I correct??
What is a Joule in SI units?
 
CAF123 said:
What is a Joule in SI units?

1 J in SI base units is equal to 1 kg·m2/s2.

The answer was, in fact, B. kg. :smile:
 
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